Gun wad



s. c. BOND Au L16;-1932.

Gun mm Original 3115a men 1.192?

Qwwnto;

Patented Aug. 16, 1932 UNITED STATES PATENT OFFICE SAMUEL C. BOND, OF HOLLY DELAWARE, ASSIGNOR TO BOND MANUFACTURING CORPORATION, OF WILMINGTON, DELAWARE, A CORPORATION OF DELAWARE eon wan continuation of application Serial No, 171,907, filed March 1, 1927, and in Germany January 9, 1927.

This application filed April 22, 1930. Serial No. 446,403. Renewed March 23, 1982.

My invention relates to improvements in cartridge wadding and the method of wadding cartridges. This application is acontinuation of my application Serial No. 171,907, filed March 1, 1927.

The primary object of my invention is to provide a gun wad which will effect andmaintain peripheral sealing contact with the adjacent walls of cartridge and gun barrel, and

thus effect a perfect seal between the powder gases and the shot charge throughout the entire travel of the wad in the gun barrel.

It is also an object of my invention to provide an improved cartridge in which I employ a plastic wedding above the charge of powder, making a perfect initial sealing contact with the surrounding wall of the cartridge casing, so that no orifice or gap exists through which the gases can leak when the powder charge is burned or exploded. It is a further object of my invention to provide an improved method of wadding cartridges by which a plastic wad is caused to flow or expand radially to eflect initially a perfect sealing contact with the surrounding wall of the cartridge casing without subsequent swelling of the shell as invariably happens when using wadding of the usual resilient material, if lar e enough in diameter to maintain initial sea ing contact.

Further objects and objects relating to details and economies of manufacture will defi} nitely appear from the detailed description Ill shot charges to follow. In one instance, I accomplish the objects of my invention by the means set forth in the following specification. My invention is clearly defined and pointed out in the appended claims. A structure constituting a preferred embodiment of my invention is illustrated in the accompanying drawing forming a part of my specification in which:

Figure. l is a longitudinal sectional view through the breech barrel showing an un invention associated with the powder'and of the shell; a

Fig. 2 1s a similarview sho the same shell immediately after havin g wen fired.

ortion of a shot gun red shot shell disposed therein, portions of the shell'being shownin'= section to show a plastic wad embodying my and disclosing the relationship of the plastic wad with the shell wall and the gun barrel at the moment of its leaving the shell; and

Fig. 3 is a view, in perspective, of the plastic asphalt wad in the normal shape in whichit exists in a loaded shot shell.

The same reference numerals refer to the same parts throughout the several views.

Modern shot-gun cartridge casings have a metallic base with an inserted primer, and acylindrical body or shell which is usually of paper treated to render it moisture-proof.

The outer diameter of the shell is made somewhat smaller than the gun chamber in which it is to be used, to allow for variance in manufacture and to facilitate its insertion and removal from the gun chamber. Therefore,

when fired, the pressure from the powder I gases immediately expands the shell :into contact with the walls of the gun chamber, efiectively preventing gas leakage by way of the breech. As the function of the wad is to preyentgas leakage by way of the muzzle, it is essential not only that it maintain sealing contact with the shell during its expansion,

" a perfect peripheral seal with the wall of the shell casing, and to maintain under firing pressure such sealing contact with the walls of cartridge casing and gunbarrel, though the wad be moving with great velocity. It is likewise essential that after remoymg the loading pressure the wad shall not press against the sides of the paper shell, thereby causing swelling. A p or defective seal permits leakage whic not only results in loss of velocity, but, if such leakage be concentrated at any point aboutthe periphery of'the wad, ser ously disturbs the pro ected shot,r es ulting in irre'gular dispersion and. a poor pattern. I am of the opinion, therefore, that a shot-gun cartridge in which a wad is used which makes a perfect gas seal with the wall of the cartridge under initial loading pressure .and with the gun barrel,

under the high gas pressures to which it is subjected, will be superior, ballistically, to those now customarily used, both from the standpoint of velocity and pattern.

. The wads now in use are compressible but not plastic the materials used, such as felt or comminuted cork agglomerated by means of a binder, being resilient and returning to their normal form upon release of pressure. I have observed that a long cork plug which fits tightly in a tube can not easily be forced therefrom by mechanical pressure on its end, but if air under pressure be substituted therefor it will beforced between the wall of the tube and the plug, and the cork seems to be constricted by the air pressure and can be easily removed from the tube. This leads me to the conclusion that the action of the powder gases on the usual cork or felt wad is much the'same, and that the gases under high pressure are forced between the edge-of the wad and the wall of the cartridge casing or the gun barrel, constricting the wad radially and permitting leakage about its periphery, particularly in view of the fact that the wad, when starting its forward'movement, meets far greater resistance at its periphery due both to the friction at this point and the resistance of the crimp holding the over shot wad resulting in the powder bulging forward and constricting the periphery exposed to the powder allowing the gases direct access thereto. It is the object of my invention, therefore, to provide a wad of such character that the loading pressure causes it to expand radially and to snugly contact with the wall of the cartridge casing, which initial sealing contact is maintained with the wall of the cartridge casing and gun barrel, under the pressure of the powder gases, thus preventing leakage of the latter pastthe wad.

propose, therefore, to provide a gun wad having plasticity so that the wad may be permanently deformed under loading pressure to effect, initially, perfect sealing contact with the wall of the cartridge casing, and to maintain such peripheral sealing contact with the surrounding wall under the pressure of the powder gases. Due to the inertia of the shot load, the pressure acting upon the rear face of a plastic and substantially noncompressible wadwill cause it to tend to extrude or expand radially to maintain sealing contact with its surrounding wall underfiring pressure. upon the rear face, the greater will be the pressure of contact with the surrounding wall, even with the middle bulged forward, due to the plastic or fluid nature of the wad material.- Thus it will be understood that the constriction phenomenon noticed with regard to plugs of cork, felt, and other compressible materials will not be found to exist in thle case of plugs composed of plastic materia The greater the pressurewithout the occurrence of rather dangerous pressure peaks,and, as a consequence, a compressible'means has customarily been provided in the shell, adjacent thepowder space, V

to yield under initialypressure and eliminate or reduce the pressure peak. This compressible means might be placed in the base about the primer, but has generally been incor porated in the wad itself, either by interpo= sition between layers of more rigid sealing material, or by formation of the wad from a material having resilience, such as felt or finely ground cork particles cemented togeth er with a binder. This volume-decreasing character of the wad, will, for the lack of a better word, be termed resiliency, it being of little moment whether the wad returns to its originalsize after it leaves the gun.

While it is the primary object of my invention to provide a gun wad having plasticity, whereby a perfect peripheral gas seal can be initially efi'ected and will be maintained durin the entire movement of the shot column, it is a further object of my. invention to provide in such a wad, the requisite amount of resiliency.

Referring to the numbered parts of the drawing, there is shown in Fig. 1 the breech portion 10 of a conventional shotn in which is disposed a shot shell comprising a metal base 11 having a primer (not shown), a shell wall 12 of impregnated paper, a powder charge 13, and a shot charge 14 separated by a plastic wad 15 comp sed primarily of plastic asphalt to which s added a relatively small percentage of pataflin and a relatively small amount of 'comminuted cork. A pair of paper disks 16, 17 are disposed one on each side the plastic wad 15 and prevent contamination of the shot and powder charges with the plastic substance of the wad 15. The

shot charge 14 is retained by a heavy paper disk 18 over which the edge of the shell wall 12 is crimped. In Fig. 2, which shows the relative positions of the several elements im-' mediately after the shell has been fired, the

powder charge 13 is undergoing combustion,

the plastic wad 15 is transferring its peripheral seal from the shell wall 12 to the bore of the barrel without leakage due to its flowable, plastic character, and the shot charge 14 has been started on its travel through the barrel.

I accomplish the primary object of my invention by the use of a plastic wad containing a large percentage of asphalt such as is obtained as a residue from the distillation of crude petroleum. I have found that the asphalt, commercially known as Texaco #14, which is a petroleum asphalt having a melting point by the ball and ring method of from 275 degrees to 300 degrees Fahrenheit, is especially well suited for this use. An as phalt of this character has a degree of plasticity under normal gun temperatures and pressures which renders a wad composed thereof capable of excellent contact with shell and barrel.

However, any material having the requisite plasticity to dilate under thereof.

loading pressure and under firing temperatures and pressures could be used in lieu While a wad formed solely of plastic material would be ideal, if cartridges were loadi ed with slow burning powder of low initial pressures, or in cartridges employing for example, a cushion base resilient means, it is desirable, with cartridges and powders as now made, to provide resiliency in the wad itself. I, therefore, contemplate, in accordance with my invention, the' incorporation with the plastic material of the wad, of a quantity of resilient material sufficient to absorb initial high pressures developed by the powder, yet insufiicient to materially reduce the plasticity of the wad mass as a whole with the resultant impairment of the seal. Any of the known resilient mate-' rials could be thus admixed with the plastic material employed to effect this piirpose. In actual practice, I have found comminuted cork to be most satisfactory for use with a plastic material such as asphalt, due to the fact that the asphalt serves also as a binder for the cork particles. The cork, if used, need not be composed of any fixed sized particles, but they are preferably of such size as to leave air cells therein, which are. compressible and provide considerable resiliency.

In all gun wads it is expedient to provide.

a lubricant which not only diminishes wad friction with the gun barrel, but by coating reduces leading thereof to a minimum.

prefer paraffin as the lubricating material for the reason that it is somewhat plastic, has binding qualities and is a valuable waterproofing agent. The paraflin is preferably mixed with the other components of the wad previous to its formation, although the wad could be merely coated therewith.

In employing wads of the present composition in cartridges loaded with the usual quantities of powder and shot used in present day loads with felt wads, it has been found that,

cork granules capable of passing through 15-30 screens mixed with a mixture of eight parts of asphalt to twoparts of paraffin in the proportions of one and one tenth part of cork to two parts of the asphalt and paraffin mixture, by weight, has given very satis-.

factory results where the wad has been made up by compression in a suitably heated mold. With the present composition, however, the

' wads need not be individually formed at a time prior to the loading of the shell, it being possible to feed proper quantities of the corn- It is of the utmost importance position directly into the shell on top of the powder and by means of a suitable plunger compress the same therein so that the wad is formed in situ in the cartridge. Where this methodof formingthe wads'is followed, it has been found thatthe best results may be obtained by mixing oneand one tenth parts of the granulated cork withone part paraffin and adding to this mixture one part of a composite mixture comprisin eightparts of asphalt andtwo parts, para n. Best results, when forming the Wed in situ, may be obtained by separating the Wad material from the powder and the shot'bythe insertion of two small paper discs To secure the best results, I have found it very important that a perfect sealing contact should be effected initially between the plustic wad and the surrounding wall of the cartridge casing. I propose to load the cartridge casing with the powder charge, to assemble a small paper disc above this, and then to place above such disc my im roved plastic wad which has been roughly ormed to such dimensions that'it may be assembled readily in the cartridge. aving positioned the rough-formed wad it is then subjected to a loading pressure sufiicient to cause the material of the wad to flow or expand radially into perfect sealing contact with the surrounding wall of the cartridge casing throughout its periphery. With a plastic wad of the composition herein described, of the size required for a 12-gauge shell, I have found that a loading pressure of 185 pounds will efiect the perfect initi l sealing contact desired. This having been effected, the loading of the cartridge may be completed in the usual manner, as by the insertion of-the shot charge above the wad and separated by it from the powder charge.

If desired, the rough-formed wad or the wadding composition may be heated before assembly in the cartridge, thus increasing its plasticity so that less pressure is required to ing wall.

to effect this initial sealing contact between the wad and easing, because, if any orifices or gaps exist initially between the powder and the shot to which the powder gases may have access, such orifices or gaps will continue and increase and I the gas pressure will not'be effective to close such gaps and stop the leakage. A perfect initial sealing contact is, therefore, a prerequisite to the effective use of a plastic wad. My

invention comprises, then, a novel cartridge in which a plastic wad assembled in the cartridge casingabove the powder charge has been expanded or caused to flow radially to elfect initially. a perfect sealing contact with the casing wall. p

It will be apparent that by varying the 1 proportions of the materials imparting resiliency to thewadding composition or the mai'terials imparting other characteristics there- '--to', suchas the wax and asphaltum, or by changing; the density of the composition a whole, or both, the ballistics of the fired ch'arge may be controlled. In other words, ,so'far as the density is concerned, variance 'ofthe pressureutilized informing the wad 3 I'nay, under circumstances, serve as acontrol of the pressure or velocity, or both, when -the charge is fired.

It will be seen that I have provided a gun "wad which, in its broad aspect, provides as more perfect seal by reason of its plasticity;

fund-that I have further provided, byincorpor'ation with the plastic wad, elements ad- -mirably adapting it for use with the high power, rapid burning powders employed 1n the modernshot-gun cartridge.

' I am aware that the materials and propo'rtions herein disclosed may be changed {considerably without departing from the spirit of my invention. I, therefore, claim giny invention broadly as indicated by the ap- "pended claims.

' What I claim is: '11 ,A substantially non-compressible carr 'tridge plug .or wad of relatively high plas- -ti'city, consisting of cork, paraflin and asphaltum, the asphaltum being in at least a semi-fluid state. f2. A' substantially non-compressible cartridge plug or wad of relatively high plasticity-, comprising cork particles of such size as to have air cells therein, asphaltum and parafiin, the 'asphaltum being present in a.

semi-fluid condition. p

-,3. A' granular composition for forming "cartridge plugs or wads, said composition consisting of cellular material, as haltum in l 'asemi-fiuid condition and para 11, the pro- I portion of cellular material being such as to J render the resulting wad substantially non'- J "compressible and the proportion of asphaltum and paraffin being such that the result- 'ing wad will possess a high degree of plasticit n j I 4. A- granular composition for forming cartridge plugs or wads composed of cork, asphaltum in a semi-fluid'condition and par 'alfin, the asphaltum and parafiin constitutin Qmore than fifty per cent of the volume 0 'the composition. a 1 5; A granular com osition for forming,

cartridge plugs or w s composed of particle's of cellular material, asphaltum in a semiffluid condition and parafiin, the asphaitum and paraflin constituting more than'fifty per cent of the volume of the composition.

I SAMUEL O. BOND. 

